Open Stack

Hey all!

We're adding a little bit of code to pbr to make the auto-generated
ChangeLog files a bit more useful. Currently, they are just the git
changelog, which is kinda useless. So we wrote this:

https://review.openstack.org/#/c/52367/

which produces output like this:

http://paste.openstack.org/show/49999  # on a tag
and
http://paste.openstack.org/show/50001  # not on a tag

It underscores the need for commit subjects to communicate something,
which is a good thing.

With that there, it makes changes like:
* Updated from global requirements
and
* Update my mailmap

Kinda lame in the changelog. So we were thinking - what if we recognized
one or more subject tags to skip things going into the ChangeLog file.
My first thought was:

NIT:  # use this for tiny commits that are not really worth changelogging

and

AUTO: # use for commits generated by our machines, such as the global
requirements sync or the Translations sync.

What do people think? Should we bother? Are those good? Would something
else be better? It's sort of an opt-in feature, so adding it SHOULDN'T
bork too many people.

Thoughts?
Monty